Thermoplastic resins are lightweight and easy to process and thus used in containers, pipes and the like of various shapes. Particularly, polyolefin resins are used in, for example, containers for storing organic solvents and pipes for transferring organic solvents therethrough.
However, thermoplastic resins, because of their excellent electrical insulation properties, have a characteristic feature of being easily electrically charged by friction and the like. Such electrification presents a risk of ignition or explosion of an organic solvent or flammable gas that is stored in the containers or passed through the pipes. Further, in the cases of medical containers, pipes and the like (e.g., containers for storing rubbing alcohol), attachment of dust caused by an electrostatic charge is not preferred also from the hygiene standpoint.
Antistatic agents are used for the purpose of inhibiting such electrification of containers and pipes. For example, Patent Documents 1 and 2 describe the use of a polyhydric alcohol ester (e.g., glycerin monostearate) as an antistatic agent in a container made of a polyolefin resin.
It is generally known to obtain fibers and filaments from a polyolefin resin, and nonwoven fabrics are produced from such fibers. However, since polyolefin resins have electrical insulation properties, and there is a problem of being easily electrically charged by friction and the like and thereby attracting dust and dirt in the surroundings. Particularly, in workwears and the like using such nonwoven fabrics, attraction of dust and the like is problematic. Further, nonwoven fabrics are used in transport materials and packaging materials of electric/electronic components and instruments, and the generation of static electricity presents a major problem since it causes malfunction and attracts fine dust and the like.
Concerning such problems, Patent Document 3 proposes a nonwoven fabric in which antistaticity is imparted through hydrophilization by mixing a surfactant in the raw materials in advance. Further, Patent Document 4 proposes a polyolefin nonwoven fabric which contains a modified polyolefin and a surfactant as an antistatic agent. Moreover, Patent Document 5 proposes the use of a polymer-type antistatic agent such as polyether ester amide in nonwoven fabrics.